Signal Sub-network: elloumi2018asr use the raw signal of the audio clip to generate features such as MFCC and Mel Spectrogram. They are features commonly used in the design of ASR systems, particularly systems which use an acoustic model and furthermore these features aid their model performance. These signal features are passed through the m18 architecture [1]}. m18 is a popular deep convolutional neural network (CNN) used for classification with audio signal features. This CNN model has 17 convolutional+max pooling layers which is followed by global average pooling. L2 Regularization of \(1e-4\)  and Batch Normalization are added after each of the convolutional layers.
